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If the third term in the expansion of (1...

If the third term in the expansion of `(1+x)^mi s-1/8x^2,` then find the value of `mdot`

Text Solution

Verified by Experts

The correct Answer is:
`m = 1/2`
We have,
`(1+x)^(m) = 1+mx+(m(m+1))/(2!) x^(2) + "……"`
Given that the third therm is `-(1//8)^(2)`, hence
`(m(m-1))/(2)x^(2) = =1/8x^(2)`
or `4m^(2) - 4m = -1`
or `(2m-1)^(2) = 0` or `m =1/2`
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